CXCL8 and atrial fibrillation: For example, CRP increases the risk of AF by increasing calciuminflux through the inward L-type calcium channel in the atrial muscle [47, 48].Moreover, the Cag A protein produced by H. pylori stimulates gastricepithelial cells to secrete the inflammatory mediator IL-8, inducing neutrophilinfiltration and consequently causing atrial muscle damage.